I have given the question great thought (yeah right) and have concluded that the last mammal to drink would be the vampire bat.

The argument:No food or plants. That rules out survival of the herbivores, if not for the reason that they are food for the carnivores. Soon all that would be left eventually would be the carnivores, and the vegetarians who realised they were being daft. The remaining carnivores would eat each other and all that would remain would be a bat and a large carnivore (say a lion) Now you will ask why a bat would survive? well a bat can fly and is also the only carnivorous (I realise other birds eat worms and mice but that doesnt count) bird that I know of. It also feeds on fresh blood from sleeping prey. It lands on you whilst you are sleeping and releases a anaesthetic from some glands. It then makes a hole about a inch deep and laps up your blood much like a cat would 'drink'. The anaesthetic solution that is excreted also prevents blood clotting and so deprived of medical attention the victim would bleed to death in its sleep.

So I do believe that the last animal to drink would be a bat (granted blood instead of water, but that is all within the parameters of the question).

Post script:Man would be one of the first to be pushing up the daisies!

Well, in that case...my money is on the hypercarnivore. Any of the big cats. Scratch that. The nastiest animal I ever came across was a 2 ft. Martin. It ate our cats, chickens and terrorized our dog. It was a pleasure putting it down...and we had the benefit of a gun at the time.

Cockroach is not a mammal. Actualy, thinking about it MAGr's answer is genius. Because of being nocturnal it would feed at much safer time, also it would roost out of reach of any predators. Its nutritional needs are met simply with blood. The only thing is that whatever carnivor was left alive as its last remaining source of blood may outlive it through scavenging and having a longer natural lifespan, but the Bat would have a great chance on a purely 'designed for survival' basis.

I like the vampire bat hypothesis, but one problem exists though. The cage does not seem to harbor any caves or dark chambers for the vampire bat to hide in the day. Pretty dangerous for the vampire bat during daytime if so.

The vampire bat is blind...not that it is really blind, but devolved vision due to the lack of use of it at night. Echolocation is used instead. When used in the daytime, it presents 2 problems. Echolocation is much inferior to vision in light. Echolocation is also meant for the night since it is much quieter. As a result, our bat may lose its sense of direction during the day. Also, without any things to hang on, that bat will have to land on the land which puts it on the same level as mices. Since there are no natural hideouts such as grasses and caves, I assume that the animals will be kept awaken even at night. I don't think anything would become an easy victim for the bat though.

Quote: The cage does not seem to harbor any caves or dark chambers for the vampire bat to hide in the day. Pretty dangerous for the vampire bat during daytime if so.

The vampire bat is blind...not that it is really blind, but devolved vision due to the lack of use of it at night. Echolocation is used instead. When used in the daytime, it presents 2 problems. Echolocation is much inferior to vision in light. Echolocation is also meant for the night since it is much quieter. As a result, our bat may lose its sense of direction during the day. Also, without any things to hang on, that bat will have to land on the land which puts it on the same level as mices. Since there are no natural hideouts such as grasses and caves, I assume that the animals will be kept awaken even at night. I don't think anything would become an easy victim for the bat though.

Since it is a cage, it has a caged roof which provides ample footing for the bat to hang upside down (as they do).It is true that they emmit frequencies to gauge distances but I am pretty sure that they can adapt to navigating in the day time.

Quote: I assume that the animals will be kept awaken even at night. I don't think anything would become an easy victim for the bat though

I beg to differ. When a vampire bat lands on you it feels like nothing more than a breeze running through your arm hair, and with more than 1000 different animals, I doubt that the victim would be muh aroused from a breeze.

I understand the point about the caged roof. What kind of roof? Flat roof? How do you hang on a flat roof?

The problem is during the day. During the day, there are other mammals emitting sound waves too. Whether it is low as in elephant or high as in whales. The reason echolocation works is that during the night there are less sound waves.

True, it lands like a breeze. How does it feel to be like bitten? Ok, maybe it is painless. If not, vampire bats will never get to feed. LOL...stupid me.

Quote: I understand the point about the caged roof. What kind of roof? Flat roof? How do you hang on a flat roof?

Its a cage, dont knit pick!

Quote: The problem is during the day. During the day, there are other mammals emitting sound waves too. Whether it is low as in elephant or high as in whales. The reason echolocation works is that during the night there are less sound waves.

Fair enough, furry muff.the assumption is that it will keep its sleeping patterns and sleep durin g the day even if there is sun.

Quote: True, it lands like a breeze. How does it feel to be like bitten? LOL

local anaesthetic remember? The only thing that you might feel is when the running blood reaches a part of your body that has no anaesthetic on it.